<!DOCTYPE html>
<html>
<head>
    <meta http-equiv="content-type" content="text/html;charset=UTF-8">
    <title>Title</title>
    <script src="static/jquery/jquery-3.1.0.min.js"></script>
</head>
<body>
<!--注意P标签是块级标签-->
<p id="p1">鼠标穿过我</p>
</body>
<script>
    $(document).ready(
        function () {
            $("#p1").mouseenter(function () {
                alert("鼠标移动到了id=p1的元素上")
            }

        );
    });
</script>
</html>